The basic operation and structure of a land mobile radio system is well known. Land mobile radio systems typically comprise one or more radio communication units and one or more repeaters that transceive information via radio frequency (RF) communication resources. These communication resources may be narrow band frequency modulated channels, time division multiplex slots, frequency pairs, and so forth, which are sourced by a plurality of repeaters or base stations. Land mobile radio systems may be organized as trunked communication systems, where a plurality of communication resources is allocated amongst a group of users by assigning the repeaters on a communication-by-communication basis with an RF coverage area. In addition, calls made from RF communication units to landline telephones may also be placed through the use of switches connected to the PSTN (Public Switched Telephone Network) and the repeaters that source the RF communication resources.
Generally, trunked two-way RF communication systems provide mobile and portable communication units with wireless services similar to many wired communication networks. Such examples include full-duplex telephone voice communication, two-way mobile-to-mobile group dispatch communication, and two-way mobile-to-dispatcher group dispatch communication. A typical trunked communication system site, where each different site has a different physical location, is composed of a number of full-duplex repeaters, each coupled to a variety of devices to support interconnection to the public telephone network, mobile-to-mobile calling, and to one or more dispatcher console positions. These devices typically provide a centralized control for the repeaters. For example, a single central controller provides radio channel signalling encode and decode functions, authorization functions, resource determination functions, and communication activity logging A single telephone interconnect switch typically provides the repeaters with an interface to one or more telephone lines to support telephone interconnect communication. In systems employing a single device that is shared among the repeaters, a failure of the single device may render one or more of the desired services or functions inoperable, thus impairing communications in the system. Placing redundant devices within the system is expensive and an inefficient use of space and resources.
Accordingly, there is a need for a communication system that efficiently covers a large area while providing dynamic and flexible allocation of distributed call control functions. There is also a need for a communication system that provides recovery for failed network nodes.